Such an access node is generally known in the art. It is for instance a well-known Digital Subscriber Line Access Multiplexer DSLAM.
Subscriber access networks comprising an access node are evolving to a multi-service architecture, while trying to replace Asynchronous Transfer Mode ATM with Ethernet for cost reasons. To support a multi-service architecture, ATM-like features must be added to Ethernet, such as “flow awareness”. This is the ability to treat traffic differently depending on the subscriber to whom it belongs, and the type of service it represents.
To date, Quality-of-Service QoS, policing and forwarding decisions are made in the access node by means of tunnel-based protocols, such as ATM, Point-to-Point Protocol over ATM PPPoA, and Point-to-Point Protocol over Ethernet PPPoE, or Differentiated Services DiffServ labeling techniques.
The mechanism relies on correct encapsulation or labeling at the customer side and at the service provider side. There is no possibility to insert traffic into a tunnel at an intermediate point, as may be required for multicast. There is no possibility to dynamically increase or decrease the number of quality-of-service levels at an intermediate point.
Furthermore, the known access nodes always operate at a single layer of the network for all traffic: either layer 2 (Ethernet switch) or layer 3 (Internet Protocol IP router).
An object of the present invention is to introduce the concept of “flow awareness”, well known in the field of ATM and IP, to an access node, as for instance an Ethernet DSLAM.